The purpose of the Cell Imaging Core is to provide access to equipment and technical expertise for confocal microscopy, combined confocal and multi-photon microscopy, and image processing and analysis. The range of experiments that will take advantage of this core include immunofluorescence, imaging of GFP, DsRed, RFP, and other organelle- and protein-specific dyes, time-lapse confocal microscopy, calcium imaging, and confocal imaging combined with multi-photon flash photolysis of caged compounds. This Core will take advantage of the medical school's existing Center for Cell and Molecular Imaging in order to provide these services. Equipment in the core will include three Zeiss LSM 510 confocal microscopes and two PCs for off-line image processing and data analysis. The first of the three confocal microscopes is a standard point-scanning system with three detection channels, while the second is equipped with a META detector for spectral deconvolution, and the third has nonlinear optics, non-descanned detectors, and is equipped with a Spectra-Physics 10 watt tunable femtosecond-pulsed titaniurrrsapphire laser for multiphoton excitation. This Core also will provide a Research Support Specialist who is experienced in confocal and multi-photon microscopy, plus a Research Biotechnologist who has experience with lasers, optics and microscopy design. The Research Support Specialist will assist members of each project with all experiments requiring the use of this core facility, while the Research Biotechnologist will work with project members to design new optical imaging methods and techniques that relate to the research aims of the PPG.